<rdar://problem/11679380> Make sure we do not fallback to software stepping when hardware stepping should work but fails to get enabled. Also removing dead code paths
<rdar://problem/11679380> Make sure we do not fallback to software stepping when hardware stepping should work but fails to get enabled. Also removing dead code paths

git-svn-id: 4c4cc70b1ef44ba2b7963015e681894188cea27e@159322 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb